rule_of_7s_lyme: Rule of 7's for Lyme Meningitis

In cliot: Clinical Indices and Outcomes Tools

Rule of 7's for Lyme Meningitis

Description

Calculates the Rule of 7's to stratify the risk of Lyme meningitis in children presenting with aseptic meningitis. A patient is classified as "Low Risk" if they meet all three criteria: Headache duration < 7 days, CSF mononuclear cells < 70%, and absence of 7th cranial nerve palsy. Failure of any criterion warrants further investigation for Lyme disease.

Usage

rule_of_7s_lyme(headache_duration_days, csf_mononuclear_percent, seventh_nerve_palsy)

Arguments

headache_duration_days	Numeric. Duration of headache in days.
csf_mononuclear_percent	Numeric. Percentage of mononuclear cells in the Cerebrospinal Fluid (CSF).
seventh_nerve_palsy	Numeric (0 or 1). Presence of 7th cranial nerve palsy (facial palsy). (1 = Yes).

Value

A list containing:

Risk_Classification	"Low Risk" or "Not Low Risk".
Management_Guidance	Clinical suggestions based on the risk level.
Risk_Factors_Present	List of specific criteria that failed the low-risk check.

References

Garro AC, Rutman M, Simonsen K, et al. Prospective validation of a clinical prediction model for Lyme meningitis in children. Pediatrics. 2009;123(5):e829-834. doi:10.1542/peds.2008-2425

Examples

# Example 1: Low Risk
# 3 days headache, 50% monos, No palsy
rule_of_7s_lyme(3, 50, 0)

# Example 2: High Risk (Failed duration and monos)
# 10 days headache, 80% monos, No palsy
rule_of_7s_lyme(10, 80, 0)

cliot documentation built on Dec. 1, 2025, 1:06 a.m.